.triangle(@_,@w,@c){
    width: 0px;
    height: 0px;
    overflow: hidden;
    border-width: @w;
}

.triangle(T,@w,@c){
    border-style: solid dashed dashed dashed; 
    border-color: @c transparent transparent transparent;
}

.triangle(R,@w,@c){
    border-style: dashed solid dashed dashed; 
    border-color: transparent @c transparent transparent;
}

.triangle(B,@w,@c){
    border-style: dashed dashed solid dashed; 
    border-color: transparent transparent @c transparent;
}

.triangle(L,@w,@c){
    border-style: dashed dashed dashed solid; 
    border-color: transparent transparent transparent @c;
}